textproduct: Albany

WHAT HAS CHANGED

The Frost Advisory for the Upper Hudson River Valley and the Lake George northern Saratoga Region has been canceled this morning with temps rising into the upper 30s to lower 40s.

Previous changes... An expansion of slight to low chance PoPs today for the upper level disturbance and sfc trough passage.

Some very localized areas of frost are possible again tonight for portions of the Lake George/Glens Falls and northern Saratoga Region before clouds arrive.

Skycover and PoPs were slightly adjusted Sat-Sat night with the next system from the baseline NBM.

KEY MESSAGES

1)Localized areas of frost may occur again with temps in the mid 30s for Washington, northern Saratoga, and southeast Warren Counties before clouds arrive tonight.

2) Unsettled weather pattern overnight thru the weekend into early next week with periods of showers and below normal temps, but no hydrologic impacts are expected.

DISCUSSION

KEY MESSAGE 1...Another brief window for radiative cooling (mostly clear/partly cloudy skies with light to calm winds) and temps falling into the 32-36F range may occur once again for portions of the Lake George-Glens Falls area/northern Saratoga Region tonight before clouds arrive. The growing season started on May 1st for these areas. The coverage area may be slightly smaller and the arrival of the mid and high clouds quicker. If confidence increases, then another Frost Advisory may be needed to protect tender, outdoor vegetation.

KEY MESSAGE 2...A rather active and unsettled weather pattern continues today through the weekend into early next week. Temps will be running below normal today and Sat with a mean mid and upper level trough impacting the eastern half of the CONUS. An upper level disturbance and a sfc trough will yield isolated to scattered light showers late this morning through the afternoon. The mid- level lapse rates are steep for instability showers to form. Low-level moisture is limited, but we expanded the coverage of the isolated to scattered light showers across most of eastern NY and western New England with max temps only in the mid 50s to around 60F in the valleys, and mid 40s to lower 50s over the higher terrain. Breezy W/NW winds continue 5 to 15 mph.

Tonight a brief break in the showers early on, but clouds quickly increase from the south/west with the isentropic lift increasing ahead of a warm front associated with low pressure approaching from the Great Lakes Region. Periods of showers develop late tonight and continue through most of the day Sat. The PoPs are in the 60-95% range across most of the forecast area, except the southern Dacks. It will be a cool and damp day. The rainfall may be briefly moderate in intensity, but no flooding is expected. It will be a damp and chilly day with max temps in the mid/upper 40s to mid/upper 50s over the forecast area. Rainfall amounts will range a tenth to a quarter inch from the Capital District northwest into the southern Dacks with a quarter to a half south and east.

The showers end early Sat night, but the systems cold front will be arriving for Mothers Day with another chance of showers after a cool night in the upper 30s to mid 40s. Temps may rise closer to normal May readings in the 60s to around 70F in the valleys and 50s to lower 60s over the higher terrain ahead of the frontal passage. The boundary may get hung up near the East Coast with a wave tracking along or near NY and New England Sun night through Mon. The highest probs for a quarter to half inch of rainfall are south and east of the Capital District. Some variability continues in the medium range guidance and ensembles with the track of the wave. A drier trend is possible early next week with high pressure building with still cooler than normal temps, though chances of showers increase from the mid week onward due to the influence of the broad longwave trough and a low pressure system tracking over the Ohio Valley and mid Atlantic States. Overall, a wet and unsettled spring or May pattern, but rainfall amounts do not look excessive to cause any flooding or hydro issues at this time.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

Through 12z Saturday...VFR conditions prevail across all sites this morning as clouds filter through the region. There may be patchy breaks this morning as the initial shortwave moves through, but infrared satellite shows clouds associated with the next disturbance filtering in shortly behind. With ample low- level dry air courtesy of a nearby high, ceilings should remain well within VFR thresholds everywhere today except at PSF where upslope flow could force a lowering into MVFR thresholds for a brief time this afternoon. Additionally, some light showers may enter many of the terminals this afternoon, but whether any rain actually reaches the ground is yet to be seen. We maintained PROB30s everywhere except GFL which seems to maintain hold of its dry air more efficiently that the other terminals. At those locations, virga may be enough to moisten the column and have rain actually reach the surface. But once the secondary disturbance rotates through the region this afternoon, all shower activity will cease and ceilings will begin to dissipate for the first half of the overnight period. Clouds will then be on the increase once again as our next system approaches, bringing more widespread rain to the region outside the 12z period.

Winds will increase this morning into this afternoon out of the west to northwest. Sustained speeds will reach about 10-15 kt with gusts up to 20 kt everywhere by this afternoon before the loss of daytime heating and subsequent deep mixing allow a decreasing trend into the first half of the overnight. Sustained speeds will then become rather light, under 10 kt.

Outlook...

Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: Moderate Operational Impact. Chance of SHRA. Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: Moderate Operational Impact. Chance of SHRA. Monday Night to Tuesday: No Operational Impact. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.